This invention relates to frames for framing openings in walls within which closures, such as windows or patio doors and exterior doors and the like, are to be mounted. Such frames are commonly made of wood strips or of metal strips, which strips are joined together at their adjacent ends to provide a multi-sided frame within which the closure may be mounted.
Conventional metal frames are made of extruded aluminum strips which are provided with integral channels or guides for holding and for guiding the movement of framed closures, such as window units or patio door units or exterior doors. When properly constructed and of an appropriate thickness, conventional aluminum frames are relatively rigid, strong and structurally stable. In addition, aluminum frames are general impervious to weather conditions. Wood frames, on the other hand, are subject to weathering and require frequent painting for protection. Moreover, wood frames have less strength and structural rigidity than aluminum frames, and wood frame members frequently swell or warp, which affects the ability to move the closures mounted within such frames. But wood frames are more attractive in appearance, avoid "sweating" or condensation of atmospheric moisture, feel warmer, and have other advantages over metal frames.
Thus, it would be desirable to provide a frame which possess the strength, rigidity and structural integrity of a metal frame while providing the benefits of a wood frame. Prior attempts have been made to form composite metal and wood window frames. However, such constructions have been relatively expensive, difficult to form, and otherwise are not completely satisfactory. Thus, this invention relates to an improved composite aluminum metal and wood window construction which provides the advantages of both metal and wood in a single frame.